New Zealand plans to commission about eight gigawatts of solar photovoltaic projects – more than the – by 2028, according to the government’s latest .
Authors
Alan Brent
Professor and Chair in Sustainable Energy Systems, Te Herenga Waka — Victoria University of Wellington
Catherine Iorns
Professor of Law, Te Herenga Waka — Victoria University of Wellington
Eight of these solar farms are already operational and . More than 40 are in various stages of development, with the , in excess of 150 megawatts, due to start this year.
Solar farms are not without challenges, though. They can use up farmland and change the rural landscape. However, we argue that more efficient farms can integrate solar panels and agricultural production, with economic benefits for farmers.
Given Aotearoa New Zealand’s of just under ten gigawatts, the increased generation is a significant development in the electricity sector and a positive contribution to the 2030 .
However, has focused on the potential changes to the rural landscape and the .
This is especially because solar farms are likely to be proposed for fast-track consenting. Infrastructure Minister Chris Bishop the process will “make it easier to consent new infrastructure, including renewable energy”.
We advocate a lies in “” – using agricultural land for both renewable electricity generation and farming.
Addressing concerns over land-use change
In a country where , land-use change is an obvious concern. The answer may well be agrivoltaics, which is gaining traction globally.
It means using rural land for both electricity generation and agriculture (including horticulture). Large areas of the country have been shown to be .
The major benefit of agrivoltaics is the micro-climate created under the solar arrays, with cooler temperatures during warm days and warmer temperatures at night. This results in less heat stress and less frost damage for crops.
Soils also retain more moisture, which means certain crops grow better, even with more shading. Pastoral production has seen the greatest benefits globally because animals are better protected from the elements, need less water and can access pasture in dry conditions.
Solar grazing
The integration of solar arrays with sheep farming is a major opportunity for New Zealand. Indeed, it is common practice to utilise sheep to maintain vegetation between and underneath the solar panels. This is a growing business in its own right, known as .
The economics are quite compelling. A on a Canterbury farm shows the profitability of the solar assets with an additional revenue stream for the farmer from .
Given the economic worries , this should be a definite consideration.
Addressing the hurdles
There are hurdles to realising this opportunity in a just manner. One is the upgrading of the grid to accommodate new generation capacity, a year until 2030. This figure is largely associated with the required high-voltage transmission network.
Transpower’s aims to address this issue. However, many of the smaller utility-scale solar assets will be connected to low-voltage distribution networks, which .
None of this required infrastructure upgrade is included in the . Lines companies are left to manage this issue. Effectively it means that not all farmers will be able to capitalise on the opportunity. It will be a case of “first come, first served” and a potential gold rush.
Consenting issues
This plays into the currently underway. The is currently going through the select committee and may limit comprehensive consultation with stakeholders and the careful consideration of any implications of solar projects.
A recent by the South Wairarapa District Council, for example, concluded that a proposed solar farm
is inconsistent with the other activities taking place in the rural (primary production) zone, and as such the amenity values of the rural environment would be adversely impacted.
Conversely, in the context of an application for a solar farm in Selwyn, a decision-making commissioner that our resource management system allows for, and even expects, changes in land use.
Whether changes are permissible depends on […] the planning [documents], the consideration of environmental effects and […] balanced judgement as to whether the changes meet the legislative and other requirements.
New Zealand’s for renewable electricity generation acknowledges competing values associated with the development of renewable energy resources. But it does not identify how to resolve any conflict.
The protection of highly productive agricultural land is covered by the 2022 for highly productive land, and planning officials may view conventional solar farms to be in conflict. We argue that well-designed agrivoltaic systems will resolve this conundrum.
Indeed, the decision-making panel in one agrivoltaic application in the Waikato that:
its members have seldom observed a project that delivers such significant benefits with such comparatively few adverse effects.
We would like to acknowledge the contribution Olivia Grainger and Anna Vaughan made to this research.
Alan Brent has received an internal grant (#410699) from Te Herenga Waka Victoria University of Wellington and funding from the Aotearoa New Zealand Ministry for Business, Innovation and Employment Our Land and Water (Toitū te Whenua, Toiora te Wai) ³Ô¹ÏÍøÕ¾ Science Challenge (contract C10X1901) to support the research that informs this article.
Catherine Iorns does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
